Dead dps-162kp-1 powerboard

[Danny kikkert]

I replaced the ic several times from different sellers. Unfortunaly nothing worked. Also ill tried all the tips you guys provided me. And iam greatfull for that.
This morning i walked into my shack, and the screen was cracked thanks to one of my kiddos.
So the case is close now.

[Davi.p]

First the professional channels, RS components, Distrelec, Conrad, Farnell, TME, Digikey, Mouser.. if there isn't you can watch some ebay shops specialized in IC and with a lot of good sells, UK, France usually is OK

[Danny kikkert]

What model of tv we are talking of? Where do you got the chip? Is probably a fake , scrached surface.. try a different source an don't get the cheapest..

where can i order good ones?

[Davi.p]

What do you mean for "regular shop"?

[R_J]

idd replaced the diode with ann original.
my electronics knowledge is a little poor so i guess that the te transformer have to deliver some voltage to pin 5 on the chip. but there is none!
or should the cip deliver voltage to the transformer?
on pins 2 and 3 i have normal voltage. on 1-4 none. when icheck with multimeter pins 1 and 4 have continuity.

Have you read the datasheet on the ic? Read page 14 Startup Operation. it explains how the IC produces the startup vcc voltage.

[Danny kikkert]

What model of tv we are talking of? Where do you got the chip? Is probably a fake , scrached surface.. try a different source an don't get the cheapest..

tv model is sharp lc-60le635 e.
the last chips i ordered by a regular shop, thi first one on ebay or ali.
is the chip suposed to deliver voltage to transformer pins 1-4?

[Davi.p]

What model of tv we are talking of? Where do you got the chip? Is probably a fake , scrached surface.. try a different source an don't get the cheapest..

[Danny kikkert]

Why would the transformer be dead? did you replace the shorted diode and see if the supply works? D7903 is a 15 volt zener diode NZX15B.

idd replaced the diode with ann original.
my electronics knowledge is a little poor so i guess that the te transformer have to deliver some voltage to pin 5 on the chip. but there is none!
or should the cip deliver voltage to the transformer?
on pins 2 and 3 i have normal voltage. on 1-4 none. when icheck with multimeter pins 1 and 4 have continuity.

[Davi.p]

Yes,.replace diode and replace completely transformer solder

[R_J]

Why would the transformer be dead? did you replace the shorted diode and see if the supply works? D7903 is a 15 volt zener diode NZX15B.

[Danny kikkert]

so ive installed the new ic7903, nothing! i also noticed a shorted diode D7903.
i gues the transformer is dead

[Danny kikkert]

Any update on this??

Today I received new ic, I'll keep you updated

[nomoresonys]

Any update on this??

[Danny kikkert]

Hi, about what R-J says, that IC7903 has startup current on pin 5, sound strange to me, i have not searched datasheets, based on photos, i see that Pin 5 takes current only from aux winding of transformer, usually those type of chips takes the startup from the primary winding of transformer, after the normal current on pin 5, i suggest Danny to check the original IC7903 for short on pins 1,8, if there is, check the R7907, the pink one near the big PFC inductor, it must be opened.. replace it and test the board, preferably with lamp in series..

PS: i see no signs of counterfeit, you can use the actual one for me..

Thanks, I always test with a lamp in series, I desolderd most components in that area and tested them. They tested fine.

On the transformer I get B+ voltage on pin 2-3, but on pin 1-4 nothing, the trafo also has no shorts.

On the cirquitry of ic 7902 also everything tested fine but also there is no voltage.

Is it possible that the voltage needed for that circuit comes from ic 7801?

[Davi.p]

Hi, about what R-J says, that IC7903 has startup current on pin 5, sound strange to me, i have not searched datasheets, based on photos, i see that Pin 5 takes current only from aux winding of transformer, usually those type of chips takes the startup from the primary winding of transformer, after the normal current on pin 5, i suggest Danny to check the original IC7903 for short on pins 1,8, if there is, check the R7907, the pink one near the big PFC inductor, it must be opened.. replace it and test the board, preferably with lamp in series..

PS: i see no signs of counterfeit, you can use the actual one for me..

[Danny kikkert]

I don't know it for sure, I thought ebay

I just ordered new ones, just in case. Now from a shop in Germany.

[Danny kikkert]

Check the resistance of IC7903 pin 4 to 3, if it is not shorted, there may be a possible fault with ic7902 ac brown-out ic you might try removing J7018 near @5 and see if you get any vcc on pin 5 of ic7903, If you look at the datasheet you will see the startup vcc is generated by the ic internally and charges C7907
In post #3 I said to replace C7918, that should have been C7907

and as stated above, they may be fake ic's

Did you mean to remove the @5 on the photo?, pin 4 to 3 is not shorted, the caps 7918 and 7907 are fine I checked them with an esr meter and multimeter.

Greetings dannny

[Danny kikkert]

Does appear to be a fake, I don't recall that 5 in the real ones, where did you get it?

I don't know it for sure, I thought ebay

[R_J]

Check the resistance of IC7903 pin 4 to 3, if it is not shorted, there may be a possible fault with ic7902 ac brown-out ic you might try removing J7018 near @5 and see if you get any vcc on pin 5 of ic7903, If you look at the datasheet you will see the startup vcc is generated by the ic internally and charges C7907
In post #3 I said to replace C7918, that should have been C7907

and as stated above, they may be fake ic's

[nomoresonys]

Does appear to be a fake, I don't recall that 5 in the real ones, where did you get it?